Back again...
I was told that it reduces the thyroxine's effectiveness/ absorption.
This also means no coffee or tea if you have milk in it. I take it first thing in the morning while I am getting Miss D's bottle, by the time she is finished her bottle I can have my morning cuppa.

If you have to go to hospital for any reason make sure you get the Dr to put in your notes that you have to have thyroxine early before breakfast.
Also make sure your chemist dose not change the brand of thyroxine as you could react differently to another brand.

Take care
Chris